// ------------------------------------------------------
// scene for shortest code contest 4
// Created November 2006
// by Christoph Hormann <chris_hormann@gmx.de>
// ------------------------------------------------------

// the function for the isosurface structure
#local X=
	function {
		pattern {
			agate
			turbulence 1
			octaves 12
		}
	}

// a simple scattering atmosphere
media {
	scattering { 2, .02 }
}

// the surface shape
isosurface {
	function {
		// negative sign turns inside out (could also use 'open' instead)
		-(
			// the base function: a modified cylinder
			sqrt(x*x+y*(y-z-x*1.6)*.9)
			-.05
			// the main structure
			-X(z/.3,y-7e-3,-x)*.03
			// additional small scale structure for large size renders
			-X(x*15,y*15,z*18)/1e3
			// scale to avoid need for max_gradient
		)/50
	}
	accuracy 1e-6
	pigment { rgb .8 }
	scale 6
}

// a point light to illuminate the whole thing
light_source {
	7+9*z
	<8,4,3>
}